钙离子信号是细胞中最重要的第二信使。细胞内亚细胞钙库通过钙离子通道和调节蛋白调节胞内自由钙离子水平，参与和调控了几乎所有细胞水平的生命活动。然而钙离子信号作用的核心区域细胞核是否存在钙存储，以及细胞核与其它亚细胞钙存储相互调控的机制，至今仍然未知。本项目提出使用飞秒激光刺激技术，研究紧聚焦(tightly-focused)的飞秒激光在微米和毫秒的时空尺度上刺激亚细胞结构的技术与机制，实现精确而相对孤立地调控细胞核等各个亚细胞水平的钙存储，揭示细胞核是否存在稳定的钙库，阐明细胞核与内质网等亚细胞结构之间的钙离子相互作用的调节机制，进而实现激光对若干重要细胞过程的直接控制。此项研究有望填补细胞钙信号研究中细胞核这个空白，对细胞钙理论，细胞信号通路的研究，以及细胞免疫与发育等领域都具有重要理论价值；这种非侵入的激光刺激调控方法也在细胞钙信号研究中具有广阔的应用前景。

Ca2+ is the most important second messenger in cells. The subcellular Ca2+ stores regulate intracellular Ca2+ level dynamics by Ca2+ channels and proteins to further mediate or control most life processes of cells. However, Ca2+ signaling in nucleus, the key component of cells, remains unknown in terms of the exsist of Ca2+ store inside and the Ca2+ regulating mechanism between nucleus and other subcellular structures. In this proposal, we plan to develop the technology of photostimulation on subcellular structures at the micron and millisecond level by the tightly-focused femtosecond laser, investigate the mechanism of photostimulation, and control the Ca2+ store in each subcellular component precisely and independently. In this way, this research aims to reveal the exsist of stable Ca2+ store in nucleus, clarify the Ca2+ regulating mechanism between nucleus and other subcellular Ca2+ stores like endoplasmic reticulum, and finally control some key cell processes directly by the femtosecond-laser stimulation. This proposed research is of great potential to bridge the gap of nuclear Ca2+ in cell calcium research. It thus can provide significant biological insights for cell immunity and development and simultaneously a potential optical method for practical applications in cell biology.